Magnesium QE22A-T6,UNS M18220;,E FOUR

Product Datasheet: Magnesium QE22A-T6 (UNS M18220)** **High-Strength Elevated Temperature Magnesium Casting Alloy** --- #### **1. Overview** Magnesium QE22A-T6 (UNS M18220) is a high-strength magnesium casting alloy strengthened by silver and rare earth element additions. In the T6 temper (solution heat-treated and artificially aged), this alloy offers an excellent combination of room and elevated temperature strength, good castability, and superior creep resistance compared to conventional magnesium alloys. Originally developed for aerospace applications, QE22A maintains its mechanical properties at temperatures up to 250°C (480°F), making it suitable for demanding powertrain and structural components. --- #### **2. Key Features & Advantages** - **Excellent Elevated Temperature Strength:** Maintains properties up to 250°C (480°F) - **Superior Creep Resistance:** Outperforms most magnesium alloys under sustained load at high temperatures - **Good Castability:** Suitable for sand, permanent mold, and investment casting processes - **High Yield Strength:** Offers excellent strength-to-weight ratio - **Good Pressure Tightness:** Minimal porosity in properly cast components - **Improved Corrosion Resistance:** Better than many high-strength magnesium alloys --- #### **3. Chemical Composition (Weight %)** | Element | Mg (Balance) | Ag | Rare Earth (RE) | Zr | Zn (max) | Other (max) | |---------------|--------------|------------|-----------------|------------|------------|-------------| | **Content (%)** | - | 1.8-2.5 | 1.5-2.5 | 0.4-1.0 | 0.2 | 0.30 total | *Note: Rare earth elements typically include neodymium and praseodymium. Zirconium serves as a grain refiner.* --- #### **4. Typical Physical & Mechanical Properties (T6 Temper)** | Property | Value | Condition / Remarks | |---------------------------|------------------------------|---------------------| | **Density** | 1.81 g/cm³ (0.065 lb/in³) | | | **Melting Range** | 545-645°C (1013-1193°F) | | | **Thermal Conductivity** | 113 W/m·K | At 25°C | | **Coefficient of Thermal Expansion** | 26.1 × 10⁻⁶/°C | 20-100°C | | **Ultimate Tensile Strength** | 240 MPa (35 ksi) | Sand Cast | | **Tensile Yield Strength**| 185 MPa (27 ksi) | 0.2% offset | | **Compressive Yield Strength** | 185 MPa (27 ksi) | | | **Elongation** | 2-4% | In 2 inches | | **Shear Strength** | 145 MPa (21 ksi) | | | **Fatigue Strength** | 97 MPa (14 ksi) | 5×10⁸ cycles | | **Elastic Modulus** | 45 GPa (6.5×10⁶ psi) | | | **Hardness** | 70-80 HB | | --- #### **5. International Standards** QE22A-T6 is specified in the following standards: - **ASTM B80:** Standard Specification for Magnesium-Alloy Sand Castings - **ASTM B199:** Specification for Magnesium-Alloy Permanent Mold Castings - **AMS 4418:** Aerospace Material Specification for Castings - **UNS M18220:** Unified Numbering System designation - **ISO 16220:** Magnesium and magnesium alloys - Castings --- #### **6. Applications** - **Aerospace Components:** - Gearbox housings and transmission cases - Engine accessory housings - Helicopter transmission casings - Missile and radar components - **Racing & High-Performance Automotive:** - Engine blocks and cylinder heads - Transmission cases - Suspension components - **Defense Applications:** - Portable military equipment housings - Weapon system components - **Specialized Industrial:** - High-temperature pump housings - Compressor components --- #### **7. Heat Treatment & Processing** - **Solution Treatment:** 525°C (977°F) for 4-8 hours followed by quenching - **Aging Treatment:** 200°C (392°F) for 8-16 hours (T6 temper) - **Casting Methods:** Suitable for sand, permanent mold, and investment casting - **Machining:** Good machinability with proper techniques - **Welding:** Weldable using TIG methods with proper filler material - **Surface Protection:** Requires conversion coatings or anodizing for corrosion protection --- #### **8. Quality Assurance** - **Microstructure:** Fine-grained with uniform dispersion of precipitates - **X-ray Inspection:** Capable of meeting aerospace quality levels - **Dye Penetrant:** Suitable for surface defect detection - **Mechanical Testing:** Certified to meet specified properties --- **Disclaimer** This technical data is for informational purposes only. Properties may vary depending on casting method, section size, and heat treatment parameters. Users should conduct appropriate testing to verify suitability for specific applications and consult relevant material specifications before use. Proper safety precautions for magnesium processing must always be followed.

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3350 gallon liquid totes Special package is available on request.